4X4 swap: various questions

[Firearmfiend]

So here it goes!

First the background:

I have a '70 C-10 that I'm converting to 4wd. Don't try and talk me into a frame
swap or anything like that, please! The rear has a 12-bolt w/ leafs that came from the factory so I don't need to worry about that.

I have aquired over the last few years a front Dana 44 and a Rockwell 221 divorced t-case from a '66 K-10 and an SM-420 from another truck. Lucky for me the ratio on the Dana matches my rear axle according to the tag on the cover. I also have a high hump tunnel cover I aquired because the truck now has a 3-speed.

I also know I might need a 4wd steering box.

The questions:

Is the frame width on a '66 close enough to my '70 so I don't have to relocate the spring perches on the axle?

Is there a way to identify the axle any further? There are no stamps on the tubes, just a few numbers cast into the center-section.

Might I fab up a cross-over steering set-up using some of my 2wd steering components or is this a pipe dream?

Should I maybe do a twin stick shifter on the Rockwell or will this work for this t-case?

Anything else you can think of, too, would be greatly appreciated!